Muscles of Lateral Pelvic Wall

Question 1

Obturator Internus

Answer 1

O: Anterolateral wall of true pelvis
I: Medial surface of greater trochanter of femur
N: Nerve to obturator internus
A: Lateral rotation of extended hip joint & abduction of flexed hip

Question 2

Piriformis

Answer 2

O: Anterior surface of sacrum bw anterior sacral foramina
I: Greater trochanter of femur
N: Branches from L5, S1, S2
A: Lateral rotation of extended hip joint & abduction of flexed hip

Question 3

Sacral Plexus

Answer 3

Sciatic (tibial and common fibular parts)
Pudendal
Superior Gluteal
Inferior Gluteal
N to Obturator Internus and Superior Gemellus
N to Quadratus Femoris and Inferior Gemellus
Posterior Femoral Cutaneous
Nerve to Piriformis
Nerves to levator ani, coccygeus, & internal/external anal sphincter

Question 3

Sciatic- Tibial Part

Answer 3

Segments: L4-S3
Motor Fx: muscles in posterior/hamstring compartment of thigh, muscles in posterior compartment of leg, muscles in sole of foot
Sensory Fx: skin on posterolateral and medial surfaces of foot and sole of foot

Question 4

Sciatic- Common Fibular Part

Answer 4

Segments: L4-S2
Motor fx: short head of biceps in posterior thigh, muscles in anterolateral compartment of leg, extensor digitorum brevis in foot
Sensory fx: skin on anterolateral surface of leg and dorsal surface of foot

Question 5

Pudendal

Answer 5

Segments: S2-S4
Motor fx: muscles in perineum (external urethral and anal sphincters and levator ani)
Sensory fx: skin of perineum, penis and clitoris

Question 6

Superior gluteal

Answer 6

Segments: L4-S1
Motor fx: gluteus medius, gluetus minimus, tensor fasciae latae

Question 7

Inferior Gluteal

Answer 7

Segments: L5-S2
Motor fx: gluteus maximus

Question 8

Nerve to Obturator Internus and Superior Gemellus

Answer 8

Segments: L5-S2
Motor fx: Obturator internus and superior gemellus

Question 9

Nerve to Quadratus Femoris and Inferior Gemellus

Answer 9

Segments: L4-S1
Motor fx: Quadratus femoris and inferior gemellus

Question 10

Posterior Femoral Cutaneous

Answer 10

Segments: S1, S3
Sensory fx: skin on posterior thigh

Question 11

Nerve to Piriformis

Answer 11

Segments: L5, S1, S2
Motor fx: Piriformis muscles

Question 12

Nerves to levator ani, coccygeus, and external anal sphincter

Answer 12

Segments: S4
Motor fx: Levator ani, coccygeus, and external anal sphincter,
Sensory fx: small patch of skin bw anus and coccyx